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A296613
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Smallest k such that either k >= n and k is a power of 2, or k >= 5n/3 and the prime divisors of k are precisely 2 and 5.
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1
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1, 2, 4, 4, 8, 8, 8, 8, 16, 16, 16, 16, 16, 16, 16, 16, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 128, 128
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OFFSET
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1,2
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COMMENTS
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First disagreement with A062383(n-1) is at n = 129.
For n > 2, a(n) is not squarefree. - Iain Fox, Dec 17 2017
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LINKS
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PROG
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(PARI) a(n) = for(k=n, +oo, if(k == 2^valuation(k, 2) || (k >= 5*n/3 && factor(k)[, 1] == [2, 5]~), return(k))) \\ Iain Fox, Dec 17 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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